The Farm-poultry . Fis. 1.—OVARY OF I-AYIN<; H I N. mother, which is its sutticient protection, andthe development is uninterrupted. In ovipar-ous animals, such as birds, the egg is enclosedin a hard protecting shell, and at a certainstage of development extruded fiom the bodyof the mother; in this case development isarrested at that point, and may, or may not,be resumed and completed The ovary of a hen during or near her layingseason presents an appearance much like thatof a cluster of fruit, and is accurately shovvnby the illustration, Fig. 1. There are, strictly,two such organs in every
The Farm-poultry . Fis. 1.—OVARY OF I-AYIN<; H I N. mother, which is its sutticient protection, andthe development is uninterrupted. In ovipar-ous animals, such as birds, the egg is enclosedin a hard protecting shell, and at a certainstage of development extruded fiom the bodyof the mother; in this case development isarrested at that point, and may, or may not,be resumed and completed The ovary of a hen during or near her layingseason presents an appearance much like thatof a cluster of fruit, and is accurately shovvnby the illustration, Fig. 1. There are, strictly,two such organs in every bird; but one. Fig. VKV AM) OVIDUCT. remains njerely rudimentary and undeveloped,the fertile one being almost always that on theleft of the spine, to which it is attached Ijymeans of the peritoneal membrane. By theovary the essential part of the egg, whichconsists of the germ, and also the yolk, isformed, each yolk being contained within athin and transparent ovisac, connected by anarrow stem or pedicle with the ovary. The rudimentary eggs are of different sizes,according to the different degree of develop-ment, and during the period of laying theyare constantly coming to maturity in due suc-cession. As the yolk becomes fully matured, theenclosing membrane or ovisac becomes grad-ually thinner, especially round its greatestdiameter or equator, which then exhibits apale zone or belt called the stigma. Finally,whether or not fecundation takes place, thesac ruptures at the stigma, and the liberatedyolk and germ, surrounded by a very thin anddelicate memlirane, is received by the funnelshaiied open
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectpoultrynortheasterns
